Personal computers are frequently used to access digital information or to assist users in creating such digital information. For example, personal computers can be used to create and access word processing documents, spreadsheets, presentations, digital media, and other forms of digital information. Some computing systems are configured to use one or more sensors to measure aspects of the physical world. However, personal computers have not yet been configured to allow application developers to take full advantage of information from such sensors in an extensible and easy to use manner.